Asteroid family

(Redirected from Asteroid clan)

An asteroid family is a population of asteroids that share similar proper orbital elements, such as semimajor axis, eccentricity, and orbital inclination. The members of the families are thought to be fragments of past asteroid collisions. An asteroid family is a more specific term than asteroid group whose members, while sharing some broad orbital characteristics, may be otherwise unrelated to each other.

Asteroid families become visible as distinct concentrations when asteroids are plotted in the proper orbital element space (ip vs ap). Some prominent families are the Vesta, Eunomia, Koronis, Eos, and Themis family located in different (colorized) regions of the asteroid belt.

General properties edit

 
Plot of proper inclination vs. eccentricity for numbered asteroids

Large prominent families contain several hundred recognized asteroids (and many more smaller objects which may be either not-yet-analyzed, or not-yet-discovered). Small, compact families may have only about ten identified members. About 33% to 35% of asteroids in the main belt are family members.

There are about 20 to 30 reliably recognized families, with several tens of less certain groupings. Most asteroid families are found in the main asteroid belt, although several family-like groups such as the Pallas family, Hungaria family, and the Phocaea family lie at smaller semi-major axis or larger inclination than the main belt.

One family has been identified associated with the dwarf planet Haumea.[1] Some studies have tried to find evidence of collisional families among the trojan asteroids, but at present the evidence is inconclusive.

Origin and evolution edit

The families are thought to form as a result of collisions between asteroids. In many or most cases the parent body was shattered, but there are also several families which resulted from a large cratering event which did not disrupt the parent body (e.g. the Vesta, Pallas, Hygiea, and Massalia families). Such cratering families typically consist of a single large body and a swarm of asteroids that are much smaller. Some families (e.g. the Flora family) have complex internal structures which are not satisfactorily explained at the moment, but may be due to several collisions in the same region at different times.

Due to the method of origin, all the members have closely matching compositions for most families. Notable exceptions are those families (such as the Vesta family) which formed from a large differentiated parent body.

Asteroid families are thought to have lifetimes of the order of a billion years, depending on various factors (e.g. smaller asteroids are lost faster). This is significantly shorter than the Solar System's age, so few if any are relics of the early Solar System. Decay of families occurs both because of slow dissipation of the orbits due to perturbations from Jupiter or other large bodies, and because of collisions between asteroids which grind them down to small bodies. Such small asteroids then become subject to perturbations such as the Yarkovsky effect that can push them towards orbital resonances with Jupiter over time. Once there, they are relatively rapidly ejected from the asteroid belt. Tentative age estimates have been obtained for some families, ranging from hundreds of millions of years to less than several million years as for the compact Karin family. Old families are thought to contain few small members, and this is the basis of the age determinations.

It is supposed that many very old families have lost all the smaller and medium-sized members, leaving only a few of the largest intact. A suggested example of such old family remains are the 9 Metis and 113 Amalthea asteroid pair. Further evidence for a large number of past families (now dispersed) comes from analysis of chemical ratios in iron meteorites. These show that there must have once been at least 50 to 100 parent bodies large enough to be differentiated, that have since been shattered to expose their cores and produce the actual meteorites (Kelley & Gaffey 2000).

Identification of members, interlopers and background asteroids edit

When the orbital elements of main belt asteroids are plotted (typically inclination vs. eccentricity, or vs. semi-major axis), a number of distinct concentrations are seen against the rather uniform distribution of non-family background asteroids. These concentrations are the asteroid families (see above). Interlopers are asteroids classified as family members based on their so-called proper orbital elements but having spectroscopic properties distinct from the bulk of the family, suggesting that they, contrary to the true family members, did not originate from the same parent body that once fragmented upon a collisional impact.

Description edit

 
Comparison: osculating Keplerian orbital elements on the left (families indistinguishable) vs. proper elements on the right (families visible).

Strictly speaking, families and their membership are identified by analysing the proper orbital elements rather than the current osculating orbital elements, which regularly fluctuate on timescales of tens of thousands of years. The proper elements are related constants of motion that remain almost constant for at least tens of millions of years, and perhaps longer.

The Japanese astronomer Kiyotsugu Hirayama (1874–1943) pioneered the estimation of proper elements for asteroids, and first identified several of the most prominent families in 1918. In his honor, asteroid families are sometimes called Hirayama families. This particularly applies to the five prominent groupings discovered by him.

Hierarchical clustering method edit

Present day computer-assisted searches have identified more than a hundred asteroid families. The most prominent algorithms have been the hierarchical clustering method (HCM), which looks for groupings with small nearest-neighbour distances in orbital element space, and wavelet analysis, which builds a density-of-asteroids map in orbital element space, and looks for density peaks.

The boundaries of the families are somewhat vague because at the edges they blend into the background density of asteroids in the main belt. For this reason the number of members even among discovered asteroids is usually only known approximately, and membership is uncertain for asteroids near the edges.

Additionally, some interlopers from the heterogeneous background asteroid population are expected even in the central regions of a family. Since the true family members caused by the collision are expected to have similar compositions, most such interlopers can in principle be recognised by spectral properties which do not match those of the bulk of family members. A prominent example is 1 Ceres, the largest asteroid, which is an interloper in the family once named after it (the Ceres family, now the Gefion family).

Spectral characteristics can also be used to determine the membership (or otherwise) of asteroids in the outer regions of a family, as has been used e.g. for the Vesta family, whose members have an unusual composition.

Family types edit

As previously mentioned, families caused by an impact that did not disrupt the parent body but only ejected fragments are called cratering families. Other terminology has been used to distinguish various types of groups which are less distinct or less statistically certain from the most prominent "nominal families" (or clusters).

Clusters, clumps, clans and tribes edit

The term cluster is also used to describe a small asteroid family, such as the Karin cluster.[2] Clumps are groupings which have relatively few members but are clearly distinct from the background (e.g. the Juno clump). Clans are groupings which merge very gradually into the background density and/or have a complex internal structure making it difficult to decide whether they are one complex group or several unrelated overlapping groups (e.g. the Flora family has been called a clan). Tribes are groups that are less certain to be statistically significant against the background either because of small density or large uncertainty in the orbital parameters of the members.

List edit

Prominent families edit

 Nysa familyVesta familyFlora familyEos familyKoronis familyEunomia familyHygiea familyThemis familyHungaria familyAsteroid family#All familiesAsteroid belt
  •   Nysa: 19,073 (4.8%)
  •   Vesta: 15,252 (3.8%)
  •   Flora: 13,786 (3.5%)
  •   Eos: 9,789 (2.5%)
  •   Koronis: 5,949 (1.5%)
  •   Eunomia: 5,670 (1.4%)
  •   Hygiea: 4,854 (1.2%)
  •   Themis: 4,782 (1.2%)
  •   Hungaria: 2,965 (0.7%)
  •   All other families: 21,500 (5.4%)
  •   Background: 295,000 (74.0%)
Distribution of the most prominent families, other families and background asteroids (up to number 398,000)[3]: 23 

Among the many asteroid families, the Eos, Eunomia, Flora, Hungaria, Hygiea, Koronis, Nysa, Themis and Vesta families are the most prominent ones in the asteroid belt. For a complete list, see § All families.

Eos family
The Eos family (adj. Eoan; 9,789 members, named after 221 Eos)
Eunomia family
The Eunomia family (adj. Eunomian; 5,670 known members, named after 15 Eunomia) is a family of S-type asteroids. It is the most prominent family in the intermediate asteroid belt and the 6th-largest family with approximately 1.4% of all main belt asteroids.[3]: 23 
Flora family
The Flora family (adj. Florian; 13,786 members, named after 8 Flora) is the 3rd-largest family. Broad in extent, it has no clear boundary and gradually fades into the surrounding background population. Several distinct groupings within the family, possibly created by later, secondary collisions. It has also been described as an asteroid clan.
Hungaria family
The Hungaria family (adj. Hungarian; 2,965 members, named after 434 Hungaria)
Hygiea family
The Hygiea family (adj. Hygiean; 4,854 members, named after 10 Hygiea)
Koronis family
The Koronis family (adj. Koronian; 5,949 members, named after 158 Koronis)
Nysa family
The Nysa family (adj. Nysian; 19,073 members, named after 44 Nysa). Alternatively named Hertha family after 135 Hertha.
Themis family
The Themis family (adj. Themistian; 4,782 members, named after 24 Themis)
Vesta family
The Vesta family (adj. Vestian; 15,252 members, named after 4 Vesta)

All families edit

In 2015, a study identified 122 notable families with a total of approximately 100,000 member asteroids, based on the entire catalog of numbered minor planets, which consisted of almost 400,000 numbered bodies at the time (see catalog index for a current listing of numbered minor planets).[3]: 23  The data has been made available at the "Small Bodies Data Ferret".[4] The first column of this table contains the family identification number or family identifier number (FIN), which is an attempt for a numerical labeling of identified families, independent of their currently used name, as a family's name may change with refined observations, leading to multiple names used in literature and to subsequent confusion.[3]: 17 

FIN Family Lbl # of Members[5] Loc.
[note 1]
Taxonomy mean-
albedo
mean a mean e mean i Parent body · Notes Cat LoMP
001 Hilda family HIL 18 rim C 0.04 3.965 0.174 8.92 153 Hilda; adj. Hildian; within the larger dynamical group with the same name.
(a–e–i: 3.7–4.2 AU; > 0.07; < 20°)
cat list
002 Schubart family SHU 531 rim C 0.03 3.966 0.191 2.92 1911 Schubart (within the dynamical Hilda group) cat list
003 Hungaria family H 1870 close E 0.35 1.944 0.078 20.87 434 Hungaria; located within the dynamical group of the same name.
(a–e–i: 1.78–2.0 AU; < 0.18; 16°–34°)
cat list
004 Hektor family HEK 16 trojan 5.204 0.054 19.02 624 Hektor (Jupiter trojan) cat list
005 Eurybates family ERY 197 trojan CP 0.06 5.204 0.044 7.42 3548 Eurybates (Jupiter trojan) cat list
006 unnamed family 006 15 trojan 0.06 5.204 0.049 31.75 9799 Thronium (Jupiter trojan) list
007 James Bond family[6] 007 1 A ASP 2.474 0.129 6.32 9007 James Bond list
008 Arkesilaos family ARK 37 trojan 5.204 0.029 8.89 20961 Arkesilaos (Jupiter trojan) cat list
009 Ennomos family ENM 30 trojan 0.06 5.204 0.041 26.79 4709 Ennomos (Jupiter trojan) cat list
010 unnamed family 010 13 trojan 0.09 5.204 0.041 24.23 (247341) 2001 UV209 (Jupiter trojan) list
401 Vesta family V 10612 A V 0.35 2.362 0.099 6.36 4 Vesta (adj. Vestian) cat list
402 Flora family
(Ariadne family)
FLO 13786 A S 0.30 2.201 0.144 5.34 8 Flora (adj. Florian), also named after 43 Ariadne; typical asteroid clan. Not a legitimate asteroid family according to Carruba and Milani, instead, the Florian core region is labelled Belgica family and Duponta family (1338), respectively.[7][8] cat list
403 Baptistina family BAP 176 A X 0.16 2.264 0.149 6.00 298 Baptistina, merges with the Belgica family (1052) at 100 m/s according to Carruba[8] cat list
404 Massalia family MAS 7820 A S 0.22 2.409 0.162 1.42 20 Massalia, adj. Massalian, a-e-i: (2.37 to 2.45; 0.12 to 0.21; 0.4 to 2.4) cat list
405 Nysa–Polana complex
(Hertha family; Eulalia family)
NYS 15983 A SFC 0.28
0.06
2.423 0.174 3.04 44 Nysa/142 Polana also known as the Hertha family (135 Hertha). Includes the Eulalia family (495 Eulalia) cat (44)
(142)
406 Erigone family ERI 1776 A CX 0.06 2.367 0.210 4.74 163 Erigone, adj. Erigonian. Can be joined with the dynamically different Martes family into a single collisional family (Src). cat list
407 Clarissa family CLA 236 A X 0.05 2.406 0.107 3.35 302 Clarissa cat list
408 Sulamitis family SUL 193 A C 0.04 2.463 0.091 5.04 752 Sulamitis cat list
409 Lucienne family LCI 142 A S 0.22 2.462 0.111 14.51 1892 Lucienne cat list
410 Euterpe family EUT 474 A S 0.26 2.347 0.187 0.72 27 Euterpe cat list
411 Datura family DAT 6 A S 0.21 2.235 0.156 5.21 1270 Datura; Recently formed family with members: (60151), (90265), (203370), (215619) and (338309) cat list
412 Lucascavin family LCA 3 A S 2.281 0.127 5.20 21509 Lucascavin; members: (180255), (209570) cat list
413 Klio family KLI 330 A C 0.07 2.362 0.193 9.38 84 Klio cat list
414 Chimaera family CIM 108 A CX 0.06 2.460 0.155 14.65 623 Chimaera cat list
415 Chaldaea family
(Salli family)
CHL 132 A C 0.07 2.376 0.236 11.60 313 Chaldaea; alt. named after 1715 Salli by Masiero cat list
416 Svea family SVE 48 A CX 0.06 2.476 0.088 16.09 329 Svea cat list
417 unnamed family 417 9 A 2.465 0.153 3.93 (108138) 2001 GB11 list
701 Phocaea family PHO 1248 A S 0.22 2.400 0.228 23.41 25 Phocaea cat list
501 Juno family JUN 1693 B S 0.25 2.669 0.232 13.34 3 Juno (adj. Junonian) cat list
502 Eunomia family EUN 9856 B S 0.19 2.644 0.148 13.08 15 Eunomia cat list
504 Nemesis family
(Liberatrix or Zdeněkhorský family)
NEM 1302 C C 0.05 2.750 0.088 5.18 128 Nemesis (adj. Nemesian); also named after 58 Concordia (adj. Concordian) and 3827 Zdeněkhorský. Formerly Liberatrix family by Zappalà (1995) and Cellino (2002) cat list
505 Adeona family ADE 2070 B C 0.07 2.673 0.169 11.71 145 Adeona cat list
506 Maria family
(Roma family)
MAR 2958 B S 0.25 2.554 0.101 15.02 170 Maria; alternatively named after 472 Roma.[9] cat list
507 Padua family
(Lydia family)
PAD 1087 C X 0.10 2.747 0.035 5.09 363 Padua; also known as Lydia family[C] · 110 Lydia · adj. Paduan; Lydian cat list
508 Aeolia family AEO 529 C X 0.17 2.742 0.168 3.49 396 Aeolia cat list
509 Chloris family CLO 120 C C 0.06 2.727 0.255 9.23 410 Chloris, adj. Chloridian cat list
510 Misa family MIS 647 B C 0.03 2.658 0.178 2.26 569 Misa, adj. Misian cat list
511 Brangäne family BRG 325 B S 0.10 2.587 0.179 9.64 606 Brangäne cat list
512 Dora family DOR 1742 C C 0.05 2.797 0.198 7.83 668 Dora, adj. Dorian cat list
513 Merxia family MRX 1263 C S 0.23 2.745 0.133 4.85 808 Merxia, adj. Merxian cat list
514 Agnia family AGN 3336 C S 0.18 2.783 0.066 3.58 847 Agnia cat list
515 Astrid family AST 548 C C 0.08 2.788 0.048 0.66 1128 Astrid, adj. Astridian cat list
516 Gefion family
(Ceres family; Minerva family)
GEF 2428 C S 0.20 2.784 0.129 9.01 1272 Gefion, adj. Gefionian; a-e-i: (2.74 to 2.82; 0.08 to 0.18; 7.4 to 10.5); also known as Ceres family (adj. Cererian) after 1 Ceres; and Minerva (adj. Minervian) family after 93 Minerva (identified interloper) cat list
517 König family KON 578 B CX 0.04 2.571 0.139 8.85 3815 König cat list
518 Rafita family RAF 775 B S 0.25 2.547 0.173 7.74 1644 Rafita, adj. Rafitian (namesake is a suspected interloper; not listed in family); members (1587) and (1658) cat list
519 Hoffmeister family HOF 2095 C CF 0.04 2.787 0.047 4.36 1726 Hoffmeister cat list
520 Iannini family IAN 150 B S 0.32 2.644 0.267 12.19 4652 Iannini cat list
521 Kazuya family KAZ 44 B S 0.21 2.568 0.141 14.56 7353 Kazuya cat list
522 Ino family INO 463 C S 0.24 2.743 0.172 13.52 173 Ino cat list
523 Emilkowalski family EMI 4 B S 0.20 2.599 0.178 17.42 14627 Emilkowalski; members: (126761), (224559) and (256124) cat list
524 Brugmansia family 524 3 B S 2.620 0.179 2.80 16598 Brugmansia; members: (190603) and (218697) cat list
525 Schulhof family SHF 5 B S 0.27 2.610 0.163 13.30 2384 Schulhof; members: (81337), (140600), (271044), (286239) cat list
526 unnamed family 526 81 C C 0.06 2.721 0.173 14.35 (53546) 2000 BY6 list
527 Lorre family LOR 2 C C 0.05 2.747 0.263 28.18 5438 Lorre; other member: (208099) cat list
528 Leonidas family LEO 111 B CX 0.07 2.681 0.193 3.81 2782 Leonidas; identical to the Vibilia family: (529/VIB) (and listed as such); (4793) cat list
530 Phaeo family PAE 146 C X 0.06 2.782 0.199 9.47 322 Phaeo cat list
531 Mitidika family MIT 653 B C 0.06 2.587 0.247 12.50 2262 Mitidika (not listed in family itself); members: (404) and (99) cat list
532 Henan family HEN 1872 B L 0.20 2.699 0.063 2.80 2085 Henan cat list
533 Hanna family HNA 280 C CX 0.05 2.807 0.180 4.17 1668 Hanna cat list
534 Karma family KRM 59 B CX 0.05 2.577 0.106 10.75 3811 Karma cat list
535 Witt family WIT 1618 C S 0.26 2.760 0.030 5.79 2732 Witt cat list
536 Xizang family XIZ 275 C 0.12 2.754 0.154 2.76 2344 Xizang cat list
537 Watsonia family WAT 83 C L 0.13 2.760 0.122 17.33 729 Watsonia cat list
538 Jones family (asteroids) JNS 22 B T 0.05 2.626 0.110 12.35 3152 Jones cat list
539 Aëria family AER 272 B X 0.17 2.649 0.056 11.76 369 Aeria cat list
540 Julia family (asteroids) JUL 33 B S 0.19 2.552 0.124 16.70 89 Julia cat list
541 Postrema family POS 108 C CX 0.05 2.738 0.242 16.53 1484 Postrema cat list
801 Pallas family PAL 45 C B 0.16 2.771 0.281 33.20 2 Pallas (adj. Palladian) cat list
802 Gallia family GAL 137 C S 0.17 2.771 0.132 25.16 148 Gallia cat list
803 Hansa family HNS 1162 B S 0.26 2.644 0.004 22.06 480 Hansa adj. Hansian; a-e-i: (~2.66; ~0.06; ~22.0°)[10] cat list
804 Gersuind family GER 415 B S 0.15 2.589 0.175 17.34 686 Gersuind cat list
805 Barcelona family BAR 346 B S 0.25 2.637 0.251 30.83 945 Barcelona cat list
806 Tina family TIN 107 C X 0.34 2.793 0.082 20.76 1222 Tina cat list
807 Brucato family BRU 41 B CX 0.06 2.605 0.132 28.90 4203 Brucato cat list
601 Hygiea family HYG 3145 G CB 0.06 3.142 0.136 5.07 10 Hygiea cat list
602 Themis family THM 5612 G C 0.07 3.134 0.152 1.08 24 Themis (adj. Themistian) cat list
603 Sylvia family SYL 191 rim X 0.05 3.485 0.054 9.76 87 Sylvia; family within Cybele group cat list
604 Meliboea family MEL 444 G C 0.05 3.119 0.186 14.54 137 Meliboea, adj. Meliboean cat list
605 Koronis family
(Lacrimosa family)
KOR 7390 D S 0.15 2.869 0.045 2.15 158 Koronis, also named after 208 Lacrimosa cat list
606 Eos family EOS 16038 E K 0.13 3.012 0.077 9.94 221 Eos cat list
607 Emma family EMA 577 F C 0.05 3.046 0.113 9.09 283 Emma cat list
608 Brasilia family BRA 845 D X 0.18 2.862 0.127 14.98 293 Brasilia, adj. Brazilian (namesake is a suspected interloper; not listed in family) cat list
609 Veritas family VER 2139 G CPD 0.07 3.174 0.066 9.06 490 Veritas, adj. Veritasian; alt: Undina (Undinian) family after 92 Undina cat list
610 Karin family KAR 541 D S 0.21 2.864 0.044 2.10 832 Karin. Recently formed family located within the Koronis family.[3]: 8, 18  cat list
611 Naëma family NAE 375 D C 0.08 2.940 0.036 11.99 845 Naëma, adj. Naëmian cat list
612 Tirela family
(Klumpkea family)
TIR 1815 G S 0.07 3.116 0.195 17.06 1400 Tirela, alternatively named after 1040 Klumpkea (AstDyS) cat list
613 Lixiaohua family
(Gantrisch family)
LIX 1241 G CX 0.04 3.153 0.201 10.06 3556 Lixiaohua; although member 3330 Gantrisch is both larger and lower numbered (src) cat list
614 Telramund family
(Klytaemnestra family)
TEL 513 E S 0.22 2.993 0.066 8.81 9506 Telramund; alternatively named after 179 Klytaemnestra by Masiero and by Milani cat list
615 unnamed family 615 159 D CX 0.17 2.848 0.106 9.14 (18405) 1993 FY12 list
616 Charis family CHA 808 D C 0.08 2.900 0.047 5.73 627 Charis cat list
617 Theobalda family THB 574 G CX 0.06 3.178 0.263 14.05 778 Theobalda, adj. Theobaldian; a-e-i: (3.16 to 3.19; 0.24 to 0.27; 14 to 15) cat list
618 Terentia family TRE 80 D C 0.07 2.932 0.072 11.11 1189 Terentia cat list
619 Lau family LAU 56 D S 0.27 2.929 0.195 6.30 10811 Lau cat list
620 Beagle family BGL 148 G C 0.09 3.155 0.154 1.34 656 Beagle. Recently formed family is located within the Themis family (all members are also listed as Themistians). Includes 7968 Elst–Pizarro.[3]: 7, 8, 18  cat list
621 Koronis family (II) K-2 246 D S 0.14 2.869 0.045 2.15 158 Koronis "second family" cat list
622 Terpsichore family TRP 138 D C 0.05 2.854 0.182 8.23 81 Terpsichore cat list
623 Fringilla family FIR 134 D X 0.05 2.914 0.093 16.68 709 Fringilla cat list
624 Durisen family DUR 27 D X 0.04 2.943 0.185 16.19 5567 Durisen cat list
625 Yakovlev family YAK 67 D C 0.05 2.870 0.290 7.89 5614 Yakovlev cat list
626 San Marcello family SAN 144 D X 0.19 2.922 0.078 12.50 7481 San Marcello cat list
627 unnamed family 627 38 D CX 0.05 2.868 0.219 16.02 (15454) 1998 YB3 list
628 unnamed family 628 248 D S 0.10 2.850 0.081 5.12 (15477) 1999 CG1 list
629 unnamed family 629 58 D S 0.21 2.939 0.118 10.73 (36256) 1999 XT17 list
630 Aegle family AEG 120 F CX 0.07 3.052 0.190 16.48 96 Aegle cat list
631 Ursula family URS 731 G CX 0.06 3.128 0.098 16.21 375 Ursula cat list
632 Elfriede family ELF 97 G C 0.05 3.189 0.061 15.87 618 Elfriede cat list
633 Itha family ITH 54 D S 0.23 2.866 0.158 12.27 918 Itha cat list
634 Inarradas family INA 43 F CX 0.07 3.050 0.184 14.51 3438 Inarradas cat list
635 Anfimov family ANF 49 F S 0.16 3.044 0.089 3.48 7468 Anfimov cat list
636 Marconia family MRC 34 F CX 0.05 3.063 0.097 2.58 1332 Marconia cat list
637 unnamed family 637 64 G CX 0.05 3.109 0.180 3.46 (106302) 2000 UJ87 list
638 Croatia family CRO 93 G X 0.07 3.133 0.026 10.66 589 Croatia cat list
639 Imhilde family IMH 43 E CX 0.05 2.983 0.237 14.59 926 Imhilde cat list
640 Gibbs family GBS 8 E 3.004 0.023 10.34 331P/Gibbs "P/2012 F5 (Gibbs)". Other members include (20674), (140429), and (177075)
641 Juliana family JLI 76 E CX 0.05 3.004 0.144 13.12 816 Juliana cat list
901 Euphrosyne family EUP 1385 G C 0.06 3.155 0.208 26.54 31 Euphrosyne cat list
902 Alauda family ALA 1294 G B 0.07 3.194 0.021 21.66 702 Alauda cat list
903 Ulla family ULA 37 rim X 0.05 3.543 0.050 17.96 909 Ulla; family within Cybele group cat list
904 Luthera family
(Kartvelia family)
LUT 232 G X 0.04 3.219 0.121 18.77 1303 Luthera; fam. is also named after 781 Kartvelia cat list
905 Armenia family ARM 67 G C 0.05 3.117 0.070 18.19 780 Armenia cat list

Other families or dynamical groups edit

Other asteroid families from miscellaneous sources (not listed in the above table), as well as non-asteroid families include:

Family Parent Cat Description
Aemilia family 159 Aemilia MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 62 members.
Alinda family 887 Alinda cat Alinda group described by projectpluto.com
Amneris family 871 Amneris cat Small family of 22 asteroids identified by Zappalà (1995).[12] Most members have been assigned to the encompassing complex of the Flora family by Nesvorný (2014).[3]
Anius family 8060 Anius MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 31 members.
Ashkova family 3460 Ashkova MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 59 members.
Astraea family 5 Astraea cat Large MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 6,169 members. Lowest-numbered members: (5), (91), (262), (355), (765) and (1121). Not a listed family by Zappalà (1995).[12] Considered a HCM-artifact by Nesvorný (2014) due to a resonant alignment (z1 = g + s − g6 − s6 = 0).[3]: 19 
Augusta family 254 Augusta cat Small family of 23 asteroids identified by Zappalà (1995).[12] Most members have been assigned to the Flora family by Nesvorný (2014).[3]
Ausonia family 63 Ausonia Single member. Unsourced. Member of the Vesta family according to AstDyS-2 and Nesvorný (2014).[3]
Bontekoe family 10654 Bontekoe MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 13 members.
Brokoff family 6769 Brokoff MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 58 members.
Bower family 1639 Bower Micro-family with 10 members as per Zappalà (1995). Adj. Bowerian. Alternative name Endymion (Endymionian) family after 342 Endymion.[C] All members: (1639), (3815), (8832), (14306), (15666), (22286), (32637), (85133), (120446) and (145685).[12] This family corresponds in large parts with the König family by Nesvorný (2014).[3]
Cindygraber family 7605 Cindygraber MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 19 members.
Clematis family 1101 Clematis cat MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 17 members. Subset of the large Alauda family as per Nesvorný (2014).[3] All members: (1101), (5360), (22044), (25982), (29963), (32240), (37628), (66174), (71688), (83362), (83790), (97516), (110030), (132961), (147858), (181960) and (223933).
Cybele group 65 Cybele cat Cybele group according to Asteroids, Meteorites, and Comets – by Linda T. Elkins-Tanton and projectpluto.com. Corresponding wiki-category lists a total of 32 members. Not a listed family in HCM by Zappalà (1995), Nesvorný (2014) and AstDyS-2 (Src), where these bodies are predominantly assigned to the background population.[12][3]
Dejanira family 157 Dejanira cat Micro-family with 5 members as per Zappalà (1995). All members: (157), (2290), (5276), (10779) and (17377).[12] All belong to the background population according to Nesvorný (2014).[3]
Devine family 3561 Devine MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 19 members.
Duponta family 1338 Duponta MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 133 members.
Epeios family 2148 Epeios Jupiter trojan family according to Roig and Gil-Hutton (2008). Part of the Menelaus clan.[13]
Eumelos family 5436 Eumelos Jupiter trojan family according to Roig and Gil-Hutton (2008). Part of the Menelaus clan.[13]
Euryalos family 4007 Euryalos Jupiter trojan family according to Roig and Gil-Hutton (2008). Part of the Menelaus clan.[13]
Faïna family 751 Faïna cat Carbonaceous family with 12 identified members as per Zappalà (1995).[12] All members: (751), (2089), (2420), (3637), (3904), (5083), (8087), (10741), (10744), (11497), (12975) and (29086). Predominantly background population with 3 bodies belonging to the stony Maria family per Nesvorný (2014). Not a listed family at AstDyS-2 (Src)
Griqua group 1362 Griqua cat Griqua group (not a collisional family) described by projectpluto.com. A marginally unstable group of asteroids observed in the 2 :1 resonance with Jupiter.
Hanskya family 1118 Hanskya MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 116 members.
Haumea family Haumea (dwarf planet) cat This is a TNO-family. As of 2017, and current categorization, the family consists of 10 members (including parent body).[D]
Helio family 895 Helio MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 50 members.
Hestia family 46 Hestia cat Nesvorný moved family (formerly FIN 503) to candidate status, and (46) to background.[3]: 19  Also background according to Milani and Knežević (AstDyS-2).
Higson family 3025 Higson MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 17 members.
Hippasos family 17492 Hippasos MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 7 members.
Huberta family 260 Huberta MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 26 members. Nesvorný moved family to candidate status.[3]: 19 
Kalchas family 4138 Kalchas Jupiter trojan family according to Roig and Gil-Hutton (2008). Part of the Menelaus clan.[13]
Laodica family 507 Laodica cat Category with 2 members. 507 Laodica and 635 Vundtia are core members of the Eos family according to AstDyS-2 (507; 635) and background asteroid per Nesvorný (507; 635), respectively.[3]
Levin family 2076 Levin MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 1534 members.
Liberatrix family 125 Liberatrix cat 3 listed members. 125 Liberatrix is a background asteroid according to AstDyS-2, and a member of the Nemesis family according to Nesvorný.[3] Background asteroid: 301 Bavaria (both AstDyS-2 and Nesvorný). 9923 Ronaldthiel is a core member of the Agnia family at AstDyS-2.
Makhaon family 3063 Makhaon Jupiter trojan family according to Roig and Gil-Hutton (2008). Part of the Menelaus clan.[13]
Marsili family 40134 Marsili MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 16 members.
Martes family 5026 Martes cat MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 481 members. Largest asteroids are members of the Erigone family according to Nesvorný (5026; 9879).[3]
Matterania family 883 Matterania MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 169 members.
Mecklenburg family 6124 Mecklenburg MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 78 members.
Melanthios family 12973 Melanthios Jupiter trojan family according to Roig and Gil-Hutton (2008). Part of the Menelaus clan.[13]
Menelaus family 1647 Menelaus Jupiter trojan family according Milani (1993).[14] Part of the Menelaus clan according to Roig and Gil-Hutton (2008).[13]
Nele family 1547 Nele MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 344 members.
Nocturna family 1298 Nocturna MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 186 members.
Nohavica family 6539 Nohavica cat Previously known as the "1982 QG" family. Second member: (9935) 1986 CP1; both are background asteroids according to AstDyS-2 and Nesvorný.
Podarkes family 13062 Podarkes Jupiter trojan family according to Roig and Gil-Hutton (2008). Part of the Menelaus clan.[13]
Prokne family 194 Prokne MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 379 members.
Reginita family 1117 Reginita cat Claimed subgroup of the Flora family. Background asteroid according to both AstDyS-2 and Nesvorný.[3]
Sinden family 10369 Sinden MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 24 members.
Takehiro family 8737 Takehiro MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 57 members. Nesvorný moved family to candidate status.[3]: 19 
Telamon family 1749 Telamon Jupiter trojan family according to Roig and Gil-Hutton (2008). Part of the Menelaus clan.[13]
Traversa family 5651 Traversa MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 56 members.
Univermoscow family 6355 Univermoscow MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 13 members.
Zhvanetskij family 5931 Zhvanetskij MBA-family (AstDys) according to Milani and Knežević (2014).[7][11] Total of 23 members.
Legend:

See also edit

Notes edit

  1. ^ "close" refers to asteroids inside the 9:2 resonance, "inner" refers to asteroids between the 9:2 and 4:1 resonance. A refers to between 4:1 and 3:1, B is 3:1 to 8:3, C is 8:3 to 5:2, D is 5:2 to 7:3, E is 7:3 to 9:4, F is 9:4 to 11:5, G is 11:5 to 2:1, "outer" refers to asteroids between the 2:1 and 11:6 resonance, and "rim" refers to asteroids beyond the 11:6 resonance.

References edit

  1. ^ Michael E. Brown, Kristina M. Barkume, Darin Ragozzine & Emily L. Schaller, A collisional family of icy objects in the Kuiper belt, Nature, 446, (March 2007), pp 294-296.
  2. ^ David Nesvorný, Brian L. Enke, William F. Bottke, Daniel D. Durda, Erik Ashaug & Derek C. Richardson Karin cluster formation by asteroid impact, Icarus 183, (2006) pp 296-311.
  3. ^ a b c d e f g h i j k l m n o p q r s t u v Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). "Identification and Dynamical Properties of Asteroid Families". Asteroids IV. pp. 297–321. arXiv:1502.01628. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. ISBN 9780816532131. S2CID 119280014.
  4. ^ "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. Archived from the original on 2 August 2017. Retrieved 22 July 2017.
  5. ^ "Asteroid families summary table for each family. Trojan and Griqua families are included". AstDyS. Retrieved 19 February 2024.
  6. ^ This is a joke by Nesvorný et al. In their Table 2 the reference is to the 1995 film, GoldenEye.
  7. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac Milani, Andrea; Cellino, Alberto; Knezevic, Zoran; Novakovic, Bojan; Spoto, Federica; Paolicchi, Paolo (September 2014). "Asteroid families classification: Exploiting very large datasets". Icarus. 239: 46–73. arXiv:1312.7702. Bibcode:2014Icar..239...46M. doi:10.1016/j.icarus.2014.05.039. S2CID 118617163.
  8. ^ a b Carruba, V.; Domingos, R. C.; Nesvorný, D.; Roig, F.; Huaman, M. E.; Souami, D. (August 2013). "A multidomain approach to asteroid families' identification". Monthly Notices of the Royal Astronomical Society. 433 (3): 2075–2096. arXiv:1305.4847. Bibcode:2013MNRAS.433.2075C. doi:10.1093/mnras/stt884.
  9. ^ Masiero, Joseph R.; Mainzer, A. K.; Bauer, J. M.; Grav, T.; Nugent, C. R.; Stevenson, R. (June 2013). "Asteroid Family Identification Using the Hierarchical Clustering Method and WISE/NEOWISE Physical Properties". The Astrophysical Journal. 770 (1): 22. arXiv:1305.1607. Bibcode:2013ApJ...770....7M. doi:10.1088/0004-637X/770/1/7. S2CID 119221614.
  10. ^ The Hansa Family: A New High-Inclination Asteroid Family
  11. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab Knezevic, Zoran; Milani, Andrea; Cellino, Alberto; Novakovic, Bojan; Spoto, Federica; Paolicchi, Paolo (July 2014). "Automated Classification of Asteroids into Families at Work". Complex Planetary Systems. 310: 130–133. Bibcode:2014IAUS..310..130K. doi:10.1017/S1743921314008035.
  12. ^ a b c d e f g Zappalà, V.; Bendjoya, Ph.; Cellino, A.; Farinella, P.; Froeschle, C. (1997). "Asteroid Dynamical Families". NASA Planetary Data System: EAR-A-5-DDR-FAMILY-V4.1. Retrieved 4 March 2020. (PDS main page)
  13. ^ a b c d e f g h i Roig, F.; Ribeiro, A. O.; Gil-Hutton, R. (June 2008). "Taxonomy of asteroid families among the Jupiter Trojans: comparison between spectroscopic data and the Sloan Digital Sky Survey colors". Astronomy and Astrophysics. 483 (3): 911–931. arXiv:0712.0046. Bibcode:2008A&A...483..911R. doi:10.1051/0004-6361:20079177. S2CID 118361725.
  14. ^ Milani, Andrea (October 1993). "The Trojan asteroid belt: Proper elements, stability, chaos and families". Celestial Mechanics and Dynamical Astronomy. 57 (1–2): 59–94. Bibcode:1993CeMDA..57...59M. doi:10.1007/BF00692462. ISSN 0923-2958. S2CID 189850747.

Further reading edit

External links edit